Tube-mill.



A. M. READ.

TUBE MILL.

APPLICATION man nic. la, 1914. nENgwEn ocT. L1, 1911.

l Patented Dec. 11, 1917.

DER M. IRED, 0F CGLUIVIBUS, OHIO, SSIGNOR TO THE JEFFREY MANUFC- 'EUG CDMPNY, 0F COLUMBUS, OHIO, A CORPOBATlON OF Oli-HO.

TUBE-MILL.

To all whom t may concern Be it known that l, ALEXANDER M. READ, a citizen of the United States, residing at Columbus, i-n the county of Franklin and State of Ghio, have invented certain new and useful Improvements in Tube-Mills, of which the following is a specification, reference being had therein to the accompanying drawing.

The invention relates especially to the grinding surface or lining of a tube mill, and the principal object of the invention is to provide a liningof novel and improved configuration and having improved means whereby the sections thereof can be readily secured to the tube casing.

In the accompanying drawing I have illustrated a tube lmill of well known construction, but it will be understood that so far as the supporting devices, the feeding ,and discharging devices, the driving devices and other parts are concerned, there can be wide variation without departing from the spirit of my invention.

0f the accompanying drawing,

Figure, 1 is a longitudinal sectional view through a tube mill embodying the invention;

Fig/2 is a transverse sectional view taken along vthe line 2-2 of Fig. 1;

Fig. 3 is a fragmentary longitudinal sectional View of an enlarged scale; and

Fig. 4; is a fragmentary transverse sectional view on an enlarged scale; and

Fig. 5 is av fragmentary sectional view on an enlarged scale on a plane parallel with the clamping washers.

Referrin to the drawing, 1 represents the cylinder, w ich can be formedof sheet metal lin the usual way. At the ends of the cylinders are the heads 2, 2, preferably formed of vcast iron and provided with-hollow trunnions 3, 3, which are mounted in the bearings 4, 4.

5 is a gear wheel secured to one of the heads and adapted for the reception of power to turn the cylinder. The material ground can be introduced through the pipe 6 and one of the hollow trunnions and can be dischargedv through the other hollow trunnion and the discharge pipe 7. These features, as above described, are well known and as to them there can be variation.

l provide for the cylinder 1 a lining which comprises a series of inward projecting Specification of Letters Patent. Patented Drang, 11d, 1911 '$1 application led December 18,1914, Serial No. 877,925. Renewed October 27, 1917. Serial No. 198,879.`

substantially hemispherical knobs, thesebeing indicated by 8, 8. The lining 'is Sectional and preferably the sections consist of bars 81L arranged longitudinally as shown. Each of the bars 8a carries a plurality (in this case four) of the said hemispherical knobs, these beingpositioned edge to edge and having diameters substantially the same as the width of the bar. rl`he lining sections are made of some suitable hard material p 4 the sort above referred to. These angle bars are of peculiar shape andare so positioned relatively to each other and to the section that their outer legs will flatly engage the inner surface of the cylinder 1 and that their inner legs, embedded in the section, will diverge so as to resist any possible tendency of the section to be radially separated from them.

The lining sections are arranged in the cylinder side by side and end to end to form a complete cylindrical surface. In order to hold the sections in place and to secure them to lthe wall of the cylinder suitable clamping means are provided for engaging the y outer legs of the angle bars 9, 9. Preferably use is made of washers 10, 10, each of which is so positioned as to engage four of the legs at the place where four of the sections are joined.` Each washer 10 is provided with a flange 10a which engages the corners of the four legs of the four angle bars and with a boss 10b which extends outward. Preferably the thickness of the boss is slightly less than the thickness of the legs of the angle bars so as to insure the contact of the Harige 10aL with all of the legs. The washer 10 1s centrally apertured and a corresponding aperture is rovided in the wall of the cylinder 1. bolt 11 extends through these apertures and has its head seated in a recess in the washer. At the outer end the bolt is provided with a nut 12 which serves to tenangle bars to clamp them against the inner surface of the cylinder.

It will be observed that the thickness of the washer 10a is such that the lining sections substantially contact with it at their outer surfaces and are thus held against any substantial movements out of their true normal positions. Each lining section is held by four of the washers above described, and it will therefore be seen that a very secure, as well as a very simple, fastening means is provided.

In order to permit the ready placing and removal of the lining sections, one of the heads 2 is provided at 13 with a manhole normally closed by the cover 14. It will be obvious that with the construction shown each lining section must be moved into its v.final position, either longitudinally or circumferentially of the cylinder surface, and to provide' for the placing or removal of the final section -it is necessary to provide an opening such as that indicated.

Suitable pebbles are provided for the interior of the cylinder, these being indicated in the drawing by 15, 15. Preferably they are formed of metal similar to that. of which the lining sections are formed.

As the mode of operation and action of tube mills of this class are well known, a specific description herein can be omitted. It is to be noted, however, that the peculiar lining surface that I have provided presents features of marked advantage over earlier constructions. The hemispherical knobs providea surface greatly increased in area, and, furthermore, provide an infinite variety of angles of contact between the surface and the pebbles and the material, thus greatly increasing the efficiency of the grinding.

Moreover, it will be seen that the rolling spheres or grinding balls on the interior are so related to the projections on the interior face of the drum that those which are contacting with the projections will settle in the interstices and tend to be raised to relatively high planes,so that their rolling down results in imparting blows or crushing actions Ato the particles that lodge in the interstices,

the projections 8*8 being arranged suiiiciently close together to produce this effect. The cylinder may be regarded as having an interior surface composed of these projections or knobs arranged in a set of series and in such way as to provide over the entire interior surface of the drum pocket-like recesses uniformly distributed over said surface, each recess having dimensions related to those of the balls as set forth to permit a ball to be seated therein and to cause the elevating of the balls to horizontal planes above those to which the balls would be normallyv carried by a smooth surfaced cylinder.

What I claim is:

l. In a tube mill, the combination with the rotatable cylinder, of a sectional lining therefor comprising a plurality of longitudinally arranged bars placed side by side and extending in a series entirely around the circumference, each bar having a row of inward projecting hemispherical knobs positioned edge to edge and having diameters substantially equal to the width of the bar.

2. In a tube mill, the combination with a rotatable cylinder, of a plurality of lining sections in the form of longitudinally arranged bars, each section having at its outer side carrier elements spaced therefrom and adapted to engage the inner surface of the cylinder, and means extending between the bars and' the carriers therefor for engaging the carriers to clamp them against the said cylinder surface.

3. In a tube mill, the combination with a rotatable cylinder, of a plurality of lining sections in the form of longitudinal bars positioned side by side, each section having at its outer side longitudinal carrier elements spaced therefrom and projecting oppositely from the central radial plane of the bar and adapted to engage the inner surface of the cylinder, and washers each engaging the inner surfaces of the carriers of a plurality of bars lto clamp them against the said cylinder surface.

4. In a tube mill, the combination with a rotatable cylinder, of a plurality of lining sections in the form of longitudinal bars positioned side by side and end to end, each section having at its outer side longitudinal carrier elements spaced therefrom and projecting oppositely from the central radial plane of the bar and adapted to engage the inner surfaces of the cylinder, and washers each engaging the inner surfaces of the corners of the carriers of four bars to clamp them against the said cylinder wall.

5. In a tube mill, the combination with a rotatable cylinder, of a plurality of lining sections in the form of longitudinally arranged cast bars, each bar having Cast thereon and projecting therefrom at. its outer side carrier-elements having parts spaced therefrom and adapted to engage the inner cylinder wall, and means extending between thel bars and the said spaced parts of the carriers for engaging the carriers to clamp them againstthe said cylinder wall.

In testimony whereof I aflix my signature in presence of two witnesses.

ALEXANDER M. READ.

Witnesses:-

DUDLEY T. FISHER, L. J. STEIN. 

